Rapid diagnosis of bacterial meningitis by the detection of a fatty acid marker in CSF with gas chromatography-mass spectrometry and selected ion monitoring.
A chemical marker of bacterial meningitis was sought by comparing derivatives of sterile cerebrospinal fluid (CSF) with cultures of organisms in spinal fluid and artificial media. The technique of gas chromatography-mass spectrometry with selected ion monitoring (GC-MS-SIM) was used, optimised for the analysis of fatty acids. Twenty candidate ions were screened, and an ion of mass: charge ratio (m/e) 268 was chosen for detection in clinical specimens. The origin of this marker is unknown, but it is probably the molecular ion of a C16:1 fatty acid. In 135 clinical specimens of CSF examined, the m/e 268 ion was found to be a useful marker for the common organisms that cause bacterial meningitis, giving a sensitivity of 88% and a specificity of 98%. The method was more rapid and more sensitive than conventional microscopy and culture, but CSF containing coagulase-negative staphylococci, Mycobacterium tuberculosis, Cryptococcus neoformans and some other uncommon pathogens gave inconsistent results. Many organisms produced characteristic ion profiles with multiple-ion monitoring, and this method of chemical analysis holds promise for the rapid diagnosis of bacterial infections to genus or species level.
French
G L
GL
Department of Microbiology, Chinese University of Hong Kong, Shatin.
Chan
C Y
CY
Poon
D
D
Cheung
S W
SW
Cheng
A F
AF
D015415:Biomarkers / Q000134:cerebrospinal fluid; D003453:Cryptococcosis / Q000134:cerebrospinal fluid / Q000175:diagnosis; D005227:Fatty Acids / Q000134:cerebrospinal fluid*; D008401:Gas Chromatography-Mass Spectrometry; D006090:Gram-Negative Bacteria / Q000032:analysis; D006094:Gram-Positive Bacteria / Q000032:analysis; D006801:Humans; D008581:Meningitis / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D009164:Mycobacterium Infections / Q000134:cerebrospinal fluid / Q000175:diagnosis; D013203:Staphylococcal Infections / Q000134:cerebrospinal fluid / Q000175:diagnosis
D015415:Biomarkers; D005227:Fatty Acids